Xanthomonas campestris pv. campestris

Last updated
Xanthomonas campestris pv. campestris
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Bacteria
Phylum: Pseudomonadota
Class: Gammaproteobacteria
Order: Xanthomonadales
Family: Xanthomonadaceae
Genus: Xanthomonas
Species: X. campestris
Pathovar:X. c.  pv. campestris
Trionomial name
Xanthomonas campestris pv. campestris
(Pammel 1895) Dowson 1939
Type strain
NCPPB 528
Synonyms

Bacillus campestris Pammel (1895)
Pseudomonas campestris (Pammel) Smith (1897)
Bacterium campestris (Pammel) Chester (1897)
Phytomonas campestris (Pammel) Bergey (1923)
Xanthomonas campestris (Pammel) Dowson (1939)

Contents

Black rot, caused by the bacterium Xanthomonas campestris pv. campestris (Xcc), is considered the most important and most destructive disease of crucifers, infecting all cultivated varieties of brassicas worldwide. [1] [2] This disease was first described by botanist and entomologist Harrison Garman in Lexington, Kentucky, US in 1889. [3] Since then, it has been found in nearly every country in which vegetable brassicas are commercially cultivated. [4]

Host infection by Xcc can occur at any stage of the plant life cycle. Characteristic symptoms of black rot caused by Xcc are V-shaped chlorotic to necrotic lesions extending from the leaf margins and blackening of vascular tissues.

The pathogen thrives in warm and humid climates and is rapidly disseminated in the field. Use of clean seed, crop rotation, and other cultural practices are the primary means of control of black rot. However, in developing countries such as those in South and Eastern Africa, black rot remains the greatest impediment to cabbage cultivation due to unreliable "clean" seed, multiple croppings annually, and high susceptibility of popular local cultivars to the disease. [5]

Hosts and symptoms

Members of the plant family Brassicaceae (Cruciferae), which includes cabbage, broccoli, cauliflower, kale, turnip, oilseed rape, mustard, radish, and the model organism Arabidopsis thaliana are affected by black rot. [1] [6] [7] [8] [2]

Host infection by Xcc causes V-shaped chlorotic to necrotic foliar lesions, vascular blackening, wilting, stunted growth, and stem rot symptoms. [1] As the pathogen proceeds from the leaf margins towards the veins, water stress and chlorotic symptoms develop due to occlusion of water-conducting vessels by bacterial exopolysaccharides and components of degraded plant cell walls. [1] [6] The darkening of vascular tissues following bacterial invasion gives the black rot disease its name. [2] Lesions produced by Xcc may serve as portals of entry for other soft-rot pathogens such as Pectobacterium carotovorum (formerly Erwinia carotovora) and Pseudomonas marginalis . [1] [2] [8]

These symptoms may be confused with fusarium wilt of cabbage (fusarium yellows), caused by the fungus Fusarium oxysporum f. sp. conglutinans. In contrast to black rot, in which the pathogen invades leaf margins and causes chlorotic to necrotic symptoms that progress downwards in the plant, fusarium wilt symptoms first develop in the lower portions of the plant and move upwards. [9] Furthermore, leaf veins invaded by Xcc turn black compared to the dark brown vein discoloration found in fusarium wilt. [9] [10]

Symptoms of black rot may vary widely among different species of crucifers. On cauliflower, Xcc infection via stomata causes black or brown specks, scratched leaf margins, black veins, and discolored curds. [11] Additionally, the severity of symptoms and aggressiveness of the disease varies between different strains of the Xcc pathogen. [1] The isolates can be differentiated into races based on the reaction of several Brassica lines after inoculation. A race structure including 5 races (0 to 4) was first proposed in 1992; [12] a revised classification model with 6 races was proposed in 2001 [13] and, more recently, the model was expanded to include nine races. [14] [15]

V-shaped chlorotic to necrotic lesion on cabbage leaf, symptomatic of infection by the black rot pathogen Xanthomonas campestris pv. campestris. Photo by David B. Langston, University of Georgia. Black rot of cabbage symptoms.jpg
V-shaped chlorotic to necrotic lesion on cabbage leaf, symptomatic of infection by the black rot pathogen Xanthomonas campestris pv. campestris. Photo by David B. Langston, University of Georgia.

Disease cycle

Life cycle of the black rot pathogen Xanthomonas campestris pv. campestris by G. Kwan. Black rot lifecycle.tif
Life cycle of the black rot pathogen Xanthomonas campestris pv. campestris by G. Kwan.


The primary source of inoculum is Xcc infected seed. [1] During germination, the seedling becomes infected through the epicotyl [1] and cotyledons may develop blackened margins, shrivel, and drop. [6] The bacteria progress through the vascular system to the young stems and leaves, where the disease manifests as V-shaped chlorotic to necrotic lesions extending from the leaf margins. Under humid conditions, bacteria present in guttation droplets can be spread by wind, rain, water splashes, and mechanical equipment to neighboring plants. [1] [6]

The natural route of invasion by Xcc is through the hydathodes, though leaf wounds caused by insects and plant roots may also be portals of entry. [1] Occasionally, infections occur through stomata. Hydathodes provide the pathogen a direct path from the leaf margins to the plant vascular system and thus systemic host infection. Invasion of the suture vein leads to production of Xcc infected seed.[ citation needed ]

Xcc can survive in plant debris in soil for up to 2 years, but not more than 6 weeks in free soil. [1] Bacteria present in plant debris can serve as a source of secondary inoculum.[ citation needed ]

Environment

Warm and wet conditions favor plant infection by Xcc and the development of disease. [6] [8] Free moisture is required for host invasion, considering that the natural route of infection is through the hydathodes.

The optimum temperature range for bacterial growth and host symptom development is between 25° and 30 °C. A slower rate of growth is observed at temperatures as low as 5 °C and up to 35 °C. [6] However, infected hosts are symptomless below 18 °C. [16]

Management

Management of black rot relies heavily on cultural practices: [6] [7]

  • Use of certified disease-free seeds and transplants
  • Hot water treatment of non-certified seeds; chemical treatments with sodium hypochlorite, hydrogen peroxide, and hot cupuric acetate or zinc sulfate may also be used
  • Control of insects
  • Crop rotation with non-cruciferous plants (3–4 years)
  • Removal of crop debris after harvest
  • Control of cruciferous weeds that may serve as reservoir for the pathogen
  • Sanitation (e.g., clean equipment, avoiding work in wet fields, etc.)

The development and use of black rot resistant cultivars has long been recognised as an important method of control, but in practice has had limited success. Resistance to the most important pathogenic races of Xcc is rare in B. oleracea (e.g., cabbage, broccoli, cauliflower); the most common and potentially useful sources of black rot resistance occur in other brassica genomes including B. rapa, B. nigra, B. napus, B. carinata and B. juncea. [17]

Resistant or tolerant cabbage cultivars are available and include: [6] [8]

  • Atlantis
  • Blueboy
  • Bravo
  • Bronco
  • Cecile
  • Defender
  • Dynasty
  • Gladiator
  • Guardian
  • Hancock
  • Ramada

Significance

Economic impact

Cabbage-family cultivation is a multi-billion dollar industry worldwide, reflecting its value as a vegetable crop, source of vegetable oil, component of fodder crop for livestock feed, and ingredient in condiments and spices. In 2007, the cabbage crop in the US exceed $413M (1.4M+ tons). [18] Black rot is considered the most important disease of cabbage and other crucifers because Xcc infections may not become apparent until the warm summer months (well after planting), the pathogen spreads rapidly, and losses due to the disease may exceed 50% in warm, wet climates. [6] The importance of using disease-free seed and/or transplants is highlighted by the fact that "as few as three infected seeds in 10,000 (0.03%) can cause black rot epidemics in a field." [6] In transplant beds, an initial infection level of 0.5% can rise to 65% in just three weeks. [2] In fact more recent work [19] indicates that spread can be much more rapid than this: with overhead gantry irrigation, spread of the pathogen greatly exceeded symptom spread to the extent that in one experiment almost 100% of the transplants were infested in a block of 15 module trays (around 4500 plants) six weeks after sowing from a single primary infector. Modelling of the rate of spread in transplants indicates that the widely used tolerance standard for seed health testing (0·01%) should be revised to 0·004%. [20]

Biotechnology

Xanthan

Xanthan is an exopolysaccharide produced by Xcc. Commercially produced xanthan is used as a thickening food additive and lubricant, amongst other industrial applications. [2]

Genomics

The genomes of three Xcc strains—ATCC 33913, B100, and 8004—have been fully sequenced and are publicly available. [21] [22] [23]

Related Research Articles

<span class="mw-page-title-main">Fusarium wilt</span> Fungal plant disease

Fusarium wilt is a common vascular wilt fungal disease, exhibiting symptoms similar to Verticillium wilt. This disease has been investigated extensively since the early years of this century. The pathogen that causes Fusarium wilt is Fusarium oxysporum. The species is further divided into formae speciales based on host plant.

<span class="mw-page-title-main">Leaf spot</span> Damaged areas of leaves

A leaf spot is a limited, discoloured, diseased area of a leaf that is caused by fungal, bacterial or viral plant diseases, or by injuries from nematodes, insects, environmental factors, toxicity or herbicides. These discoloured spots or lesions often have a centre of necrosis. Symptoms can overlap across causal agents, however differing signs and symptoms of certain pathogens can lead to the diagnosis of the type of leaf spot disease. Prolonged wet and humid conditions promote leaf spot disease and most pathogens are spread by wind, splashing rain or irrigation that carry the disease to other leaves.

<span class="mw-page-title-main">Black rot</span> Index of fungi with the same common name

Black rot is a name used for various diseases of cultivated plants caused by fungi or bacteria, producing dark brown discoloration and decay in the leaves of fruit and vegetables:

<i>Xanthomonas campestris</i> Species of bacterium

Xanthomonas campestris is a gram-negative, obligate aerobic bacterium that is a member of the Xanthomonas genus, which is a group of bacteria that are commonly known for their association with plant disease. This species includes Xanthomonas campestris pv. campestris, the cause of black rot in brassicas, one of the most important diseases of brassicas worldwide.

<i>Xanthomonas</i> Genus of bacteria

Xanthomonas is a genus of bacteria, many of which cause plant diseases. There are at least 27 plant associated Xanthomonas spp., that all together infect at least 400 plant species. Different species typically have specific host and/or tissue range and colonization strategies.

Aphanomyces euteiches is a water mould, or oomycete, plant pathogen responsible for the disease Aphanomyces root rot. The species Aphanomyces euteiches can infect a variety of legumes. Symptoms of the disease can differ among hosts but generally include reduced root volume and function, leading to stunting and chlorotic foliage. Aphanomyces root rot is an important agricultural disease in the United States, Europe, Australia, New Zealand, and Japan. Management includes using resistant crop varieties and having good soil drainage, as well as testing soil for the pathogen to avoid infected fields.

<i>Alternaria brassicae</i> Species of fungus

Alternaria brassicae is a plant pathogen able to infect most Brassica species including important crops such as broccoli, cabbage and oil seed rape. It causes damping off if infection occurs in younger plants and less severe leaf spot symptoms on infections of older plants.

Xanthomonas fragariae is a species of bacteria. It causes a leaf spot disease found in strawberries. The type strain is NCPPB1469 from Fragaria chiloensis var. ananassa.

<i>Xanthomonas vasicola</i> Species of bacterium

Xanthomonas vasicola pv. vasculorum (Xvv) is a gram-negative rod-shaped bacterium which has a single polar flagellum. It is a plant pathogen, causing both bacterial leaf streak of maize (corn) and sugarcane gumming disease. One outbreak in eucalyptus has been reported. Under experimental conditions it can infect sorghum, oats and some grass species. It is not currently a quarantine pathogen in any country, but it has already spread outside its native range and is highly adaptable to different environments.

<span class="mw-page-title-main">Napa cabbage</span> Subspecies of flowering plant

Napa cabbage is a type of Chinese cabbage originating near the Beijing region of China that is widely used in East Asian cuisine. Since the 20th century, it has also become a widespread crop in Europe, the Americas, and Australia. In much of the world, it is referred to as "Chinese cabbage". In Australia, it is sometimes referred to as "wombok".

<span class="mw-page-title-main">Banana Xanthomonas wilt</span> Bacterial disease of banana plants

Banana Xanthomonas Wilt (BXW), or banana bacterial wilt (BBW) or enset wilt is a bacterial disease caused by Xanthomonas campestris pv. musacearum. After being originally identified on a close relative of banana, Ensete ventricosum, in Ethiopia in the 1960s, BXW emanated in Uganda in 2001 affecting all types of banana cultivars. Since then BXW has been diagnosed in Central and East Africa including banana growing regions of: Rwanda, Democratic Republic of the Congo, Tanzania, Kenya, Burundi, and Uganda.

<i>Xanthomonas campestris</i> pv. <i>vesicatoria</i> Species of bacterium

Xanthomonas campestris pv. vesicatoria is a bacterium that causes bacterial leaf spot (BLS) on peppers and tomatoes. It is a gram-negative and rod-shaped. It causes symptoms throughout the above-ground portion of the plant including leaf spots, fruit spots and stem cankers. Since this bacterium cannot live in soil for more than a few weeks and survives as inoculum on plant debris, removal of dead plant material and chemical applications to living plants are considered effective control mechanisms.

Bacterial blight of cotton is a disease affecting the cotton plant resulting from infection by Xanthomonas axonopodis pathovar malvacearum (Xcm) a Gram negative, motile rod-shaped, non spore-forming bacterium with a single polar flagellum

<span class="mw-page-title-main">Beet vascular necrosis</span> Bacterial disease in beet plants

Beet vascular necrosis and rot is a soft rot disease caused by the bacterium Pectobacterium carotovorum subsp. betavasculorum, which has also been known as Pectobacterium betavasculorum and Erwinia carotovora subsp. betavasculorum. It was classified in the genus Erwinia until genetic evidence suggested that it belongs to its own group; however, the name Erwinia is still in use. As such, the disease is sometimes called Erwinia rot today. It is a very destructive disease that has been reported across the United States as well as in Egypt. Symptoms include wilting and black streaks on the leaves and petioles. It is usually not fatal to the plant, but in severe cases the beets will become hollowed and unmarketable. The bacteria is a generalist species which rots beets and other plants by secreting digestive enzymes that break down the cell wall and parenchyma tissues. The bacteria thrive in warm and wet conditions, but cannot survive long in fallow soil. However, it is able to persist for long periods of time in the rhizosphere of weeds and non-host crops. While it is difficult to eradicate, there are cultural practices that can be used to control the spread of the disease, such as avoiding injury to the plants and reducing or eliminating application of nitrogen fertilizer.

Xanthomonas axonopodis pv. manihotis is the pathogen that causes bacterial blight of cassava. Originally discovered in Brazil in 1912, the disease has followed the cultivation of cassava across the world. Among diseases which afflict cassava worldwide, bacterial blight causes the largest losses in terms of yield.

<i>Alternaria brassicicola</i> Species of fungus

Alternaria brassicicola is a fungal necrotrophic plant pathogen that causes black spot disease on a wide range of hosts, particularly in the genus of Brassica, including a number of economically important crops such as cabbage, Chinese cabbage, cauliflower, oilseeds, broccoli and canola. Although mainly known as a significant plant pathogen, it also contributes to various respiratory allergic conditions such as asthma and rhinoconjunctivitis. Despite the presence of mating genes, no sexual reproductive stage has been reported for this fungus. In terms of geography, it is most likely to be found in tropical and sub-tropical regions, but also in places with high rain and humidity such as Poland. It has also been found in Taiwan and Israel. Its main mode of propagation is vegetative. The resulting conidia reside in the soil, air and water. These spores are extremely resilient and can overwinter on crop debris and overwintering herbaceous plants.

Xanthomonas campestris pv. juglandis is an anaerobic, Gram negative, rod-shaped bacteria that can affect walnut trees though the flowers, buds, shoots, branches, trunk, and fruit. It can have devastating effects including premature fruit drop and lesions on the plant. This pathogen was first isolated by Newton B. Pierce in California in 1896 and was then named Pseudomonas juglandis. In 1905 it was reclassified as Bacterium juglandis, in 1930 it became Phytomas juglandis, and in 1939 it was named Xanthomas juglandis. The International Standards for Naming Pathovars declared it to be named Xanthomonas campestris pv. juglandis in 1980. There have been recent proposals to change the name once again to Xanthomonas arboricola pv. juglandis, but this has not yet been universally accepted.

<span class="mw-page-title-main">Alternaria leaf spot</span> Fungal plant disease

Alternaria leaf spot or Alternaria leaf blight are a group of fungal diseases in plants, that have a variety of hosts. The diseases infects common garden plants, such as cabbage, and are caused by several closely related species of fungi. Some of these fungal species target specific plants, while others have been known to target plant families. One commercially relevant plant genus that can be affected by Alternaria Leaf Spot is Brassica, as the cosmetic issues caused by symptomatic lesions can lead to rejection of crops by distributors and buyers. When certain crops such as cauliflower and broccoli are infected, the heads deteriorate and there is a complete loss of marketability. Secondary soft-rotting organisms can infect stored cabbage that has been affected by Alternaria Leaf Spot by entering through symptomatic lesions. Alternaria Leaf Spot diseases that affect Brassica species are caused by the pathogens Alternaria brassicae and Alternaria brassicicola.

<i>Xanthomonas nasturtii</i> Species of bacteria

Xanthomonas nasturii a gram-negative, obligate aerobic bacterium that like many other Xanthomonas spp. bacteria has been found associated with plants, in particular watercress. It causes black rot of watercress.

<i>Xanthomonas campestris</i> pv. <i>raphani </i> Pathovar of bacteria

Xanthomonas campestris pv. raphani is a gram-negative, obligate aerobic bacterium that like many other Xanthomonas spp. bacteria has been found associated with plants. This organism is closely related with Xanthomonas campestris pv. campestris, but causes a non-vascular leaf spot disease that is clearly distinct from black rot of brassicas.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 Alvarez AM. "Black rot of crucifers." In: Slusarenko AJ, Fraser RSS, van Loon LC (Eds.) Mechanisms of Resistance to Plant Diseases. Dordrecht, The Netherlands: Kluwer Academic Publishers, 2000. pp 21-52.
  2. 1 2 3 4 5 6 Williams PH (1980). "Black rot: a continuing threat to world crucifers". Plant Disease. 64 (8): 736–742. doi:10.1094/pd-64-736.
  3. ↑ Garman H (1890). "A bacterial disease of cabbage". Kentucky Agric Exp Stat Rep. 3: 43–46.
  4. ↑ Chupp C. “Black rot of cabbage.” Manual of Vegetable Plant Diseases. New Delhi, India : Discovery Publishing House, 2006. p. 132-133.
  5. ↑ Massomo SM, Mabagala RB, Swai IS, Hockenhull J, Mortensen CN (2004). "Evaluation of varietal resistance in cabbage against the black rot pathogen, Xanthomonas campestris pv. campestris in Tanzania". Crop Protection. 23 (4): 315–325. Bibcode:2004CrPro..23..315M. doi:10.1016/j.cropro.2003.09.001.
  6. 1 2 3 4 5 6 7 8 9 10 "Black rot of cabbage and other crucifers." Archived July 31, 2010, at the Wayback Machine Integrated Pest Management. University of Illinois Extension. Dec 1999.
  7. 1 2 Miller SA, Sahin F, Rowe RC (1996). "Black rot of crucifers" (PDF). The Ohio State University Extension. Retrieved 19 July 2016.
  8. 1 2 3 4 Seebold K, Bachi P, and Beale J. "Black rot of crucifers ." UK Cooperative Extension Service. University of Kentucky. Feb 2008.
  9. 1 2 Sherf, A. "Fusarium yellows of cabbage and related crops." New York State Cooperative Extension. Cornell University. Jan 1979.
  10. ↑ "Black rot of cabbage and other crucifers." Integrated Pest Management. University of Illinois Extension. Dec 1999.
  11. ↑ Miller SA, Sahin F, and Rowe RC. "Black rot of crucifers." Extension fact sheet HYG-3125-96. Ohio State University Extension. 1996.
  12. ↑ Kamoun S, Kamdar HV, Tola E, Kado CI (1992). "Incompatible interactions between crucifers and Xanthomonas campestris involve a vascular hypersensitive response: Role of the hrpX locus". Molecular Plant-Microbe Interactions. 5: 22–33. doi:10.1094/mpmi-5-022.
  13. ↑ Vicente JG, Conway J, Roberts SJ, Taylor JD (2001). "Identification and origin of Xanthomonas campestris pv. campestris races and related pathovars". Phytopathology. 91 (5): 492–499. doi: 10.1094/phyto.2001.91.5.492 . PMID   18943594.
  14. ↑ Jensen BD, Vicente JG, Manandhar HK, Roberts SJ (2010). "Occurrence and diversity of Xanthomonas campestris pv. campestris in vegetable brassica fields in Nepal". Plant Disease. 94 (3): 298–305. doi: 10.1094/PDIS-94-3-0298 . PMID   30754254.
  15. ↑ Fargier E, Manceau C (2007). "Pathogenicity assays restrict the species Xanthomonas campestris into three pathovars and reveal nine races within X. campestris pv. campestris". Plant Pathology. 56 (5): 805–818. doi: 10.1111/j.1365-3059.2007.01648.x .
  16. ↑ Carisse O, Wellman-Desbiens E, Toussaint V, Otis T. "Preventing black rot." Government of Canada. Horticultural Research and Development Centre. 1999.
  17. ↑ Taylor JD, Conway J, Roberts SJ, Vicente JG (2002). "Sources and origin of resistance to Xanthomonas campestris pv. campestris in Brassica genomes". Phytopathology. 92 (1): 105–111. doi: 10.1094/PHYTO.2002.92.1.105 . PMID   18944146.
  18. ↑ United States. Department of Agriculture. U.S. Cabbage Statistics - U.S. fresh cabbage: Area, yield, production, & value, 1960-2007. May 2008.
  19. ↑ Roberts SJ, Brough J, Hunter PJ (2006). "Modelling the spread of Xanthomonas campestris pv. campestris in module-raised brassica transplants". Plant Pathology. 56 (3): 391–401. doi: 10.1111/j.1365-3059.2006.01555.x .
  20. ↑ Roberts SJ (2009) Transmission and spread of Xanthomonas campestris pv. campestris in brassica transplants: implications for seed health standards. In: Biddle AJ; Cockerell V; Tomkins M; Cottey A; Cook R; Holmes W; Roberts SJ; Vickers R, Seed Treatment and Production in a Changing Environment. pp 82-85.
  21. ↑ da Silva AC, et al. (2002). "Comparison of the genomes of two Xanthomonas pathogens with differing host specificities". Nature. 417 (6887): 459–63. Bibcode:2002Natur.417..459D. doi:10.1038/417459a. PMID   12024217. S2CID   4302762.
  22. ↑ Vorhölter FJ, Schneiker S, Goesmann A, Krause L, Bekel T, Kaiser O, Linke B, Patschkowski T, Rückert C, Schmid J, Sidhu VK, Sieber V, Tauch A, Watt SA, Weisshaar B, Becker A, Niehaus K, Pühler A (2008). "The genome of Xanthomonas campestris pv. campestris B100 and its use for the reconstruction of metabolic pathways involved in xanthan biosynthesis". Journal of Biotechnology. 134 (1–2): 33–45. doi:10.1016/j.jbiotec.2007.12.013. PMID   18304669.
  23. ↑ Qian W, Jia Y, Ren SX, He YQ, Feng JX, Lu LF, Sun Q, Ying G, Tang DJ, Tang H, Wu W, Hao P, Wang L, Jiang BL, Zeng S, Gu WY, Lu G, Rong L, Tian Y, Yao Z, Fu G, Chen B, Fang R, Qiang B, Chen Z, Zhao GP, Tang JL, He C (2005). "Comparative and functional genomic analyses of the pathogenicity of phytopathogen Xanthomonas campestris pv. campestris". Genome Research. 15 (6): 757–67. doi:10.1101/gr.3378705. PMC   1142466 . PMID   15899963.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.